Improvement in expanding-bits for enlarging blast-holes



, G. FRl SB'EE Expanding Bit for Enlarging Blast-Holes.

010,162,163 V Patented April 20,13

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GIDEON FRISBEE, OF READING, PENNSYLVANIA.

IMPROVEMENT IN EXPANDING-BITS FOR ENLARGING BLAST-HOLES.

Spec fication forming part of Letters Patent No. 162,163, dated April 20, 1875; application filed November 21, 1874.

To all whom it may concern:

Be it known that I, GIDEON FRrsBEE, of Reading, in the county of Berks and State of Pennsylvania, have invented anew and useful Expanding-Bit for Enlarging Blast-Holes and I do hereby declare the following to be a full, clear, and precise description of the same, which will enable those skilled in the art to which my invention appertains to make and use it, reference being had to the accompanying drawings which form part of this specication, and in which- Fig. 1 is a longitudinal section of the expanding-bit itself, and Fig. 2 a longitudinal section of a portion of the long hole M, together with the expanded recess or enlargement of the hole X, produced by the bit aforesaid, the blasting-plug described in my patent No. lat7,253 being shown inserted.

My invention consists of the combination, with the bit 1), perforated with the hole H, of diamonds inserted in its cutting-end, the entire expanding-bit, when in action, being continuously 'rotated.

For the better information of the public, I will proceed to describe the construction of my invention, reference being had to Fig.1 of the drawin A is a hollow cylinder or casing, of metal. B is an inner rod, fitting closely within A, and having a lengthwise movement therein. N is a coupling atthe upper extremityof B, whereby B is attached to the rod of thedrill. ltunniug throughout the rod P is a holeorwaterpassage, 1. Out or formed upon the cylinder A are one or more slots, is, parallel to its axis. Passing through the rod B, or attached to it, are one or more rivets, plugs, or studs, M, pro jecting into the slots k of the cylinder A, and serving to prevent any rotation of the rod B within the cylinder, but forcing rod and cylinder to rotate together; serving also to control the thrust or lengthwise motion of the rod to the length of the slots themselves. 1) is the bit, acurved bar of metal of the form shown, carrying upon its outer end the cutting-diamonds. it is completely perforated by a hole H, which serves, in connection with the passage I in the rod B, to afford continuous communication for water with the cutting-surface. The bit is connected by a link-coupling, O, to the rod B,the connection being thepivots a a,

and being rigid in construction. The lower end of the casing A is formed with an interior solid incline, O, of the same curvature as the bit, and upon and against which the bit slides and bears as pressure is brought upon it by the feed or otherwise. The cuttin g end of the bit passes, when caused to project. through an opening, 0, in the casing A. F is a loose collar connected with the casing A by the screwpin G, which, resting upon the blasting-plug Z, forms a bearing-surface for the casin g, upon which it rotates easily.

In operation, after the long hole M is bored, the plug Z is inserted until its outer end is at the point where it is desired to enlarge the hole; then the expanding-bit hereinbefore described is inserted, attached to the rods of a drilling-machine until the collar F rests upon the plug. \Vate'r is then introduced from the drill-rods, the drilling-machine is started, r0- tating the entire device described, and the feed is applied, which, forcing down upon the rod B, forces down upon the connecting-link G, the connecting-link in turn forces down upon the curved bar D, which, by virtue of its curvature and the directing influence of the incline O, presses out laterally upon the rock, in the direction of the dotted lines Z) b, cutting as it rotates an annular groove or chamberin the rock, of the form of which X X of Fig. 2 is the section.

The extent to which the bitcau project is controlled bythe length ofthe slots kin the casing A, controlling as they do the thrust ofthe rod B; then, when it is desired to remove the drill, the feed is reversed, and the bit being thereby retracted into the casing, the entire tool can be withdrawn.

Having thus described my invention, what I claim, and desire to secure by Letters Patent of the United States, is

In a continuously-rotating expanding-drill, constructedsubstau tially as specified, the combination of the bit D perforated with the water-hole H, with the diamonds inserted in the cutting end of the bit, substantially as shown and described.

GIDEON FRISBEE. Witnesses:

JAMES R. REED, MoRGAN REED. 

